const o = (function () {
  const obj = {
    a: 1,
    b: 2,
  };
  return {
    get(key) {
      return obj[key];
    },
  };
})();

Object.defineProperty(Object.prototype, 'abc', {
  get() {
    return this;
  },
});

console.log(o.get('abc'));
